I can't comment on the individual tyre choices, or the sizes they come in, but I can comment on the Laws of Physics (particularly that bloke who had an apple land on hios head).....
.... whilst your thought process of the front wheels doing the traction and the steering is sound, the elan doesn't like better tyres to be that end
I had a bad experience with Michelins on the front and Federals on the back - fine in a straight line, or constant speed round a bend, but if you lift off anywhere in the bend the car has a tendency to shift weight (because of Isaac Newton!) to the rear and understeer ensures.
If you have less grip on the rear tyres, then the car tends to develop a habit of swapping the back end for the front
Many cars suffer from 'lift-off oversteer' (rear drive) but the elan is particularly prone to the mishap if the front wheels have a lot more grip than the back, allowing the rear end to slide.
Matched tyres all round is the best way to go, but if not, the better ones at the rear is the safest way to do it.
(I run Michelins all round on one car, and on the other I have Yokohama track tyres on the front, and Michelins on the rear - both give excellent grip in the dry, but the track tyres only really get excellent when warm, wheras the Michelins are good all the time.)
Just my 2p worth
